Reaction injection molded polyurethanes are well known in the art as described in a paper entitled "The Bayflex 110 Series--the New Generation of Rim Materials", by W. A. Ludwico and R. P. Taylor presented at the Society of Automotive Engineers Passenger Car Meeting, Detroit Mich., Sept. 26-30, 1977; a paper entitled "The Properties of High Modulus Rim Urethanes", by R. M. Gerkin and F. E. Critchfield presented at the above meeting; British Pat. No. 1,534,258 titled "Process for the Production of Elastomeric Polyurethane-Polyurea Moulded Products having a Compact Surface Skin" and a book by F. Melvin Sweeny entitled Introduction to Reaction Injection Molding, Technomics, Inc., 1979.
These systems employ, as chain extenders, diols, aromatic amines, cyanoethylated polyoxyalkylene amines and mixtures thereof.
It has been thought that as a general rule the aliphatic amines were too fast to be suitably employed in RIM urethane applications. Vanderhider and Lancaster in U.S. Pat. No. 4,269,945 discovered that low molecular weight aliphatic amine compounds could be employed as a part of the chain extender system when employed as a mixture with either or both of such materials as hydroxyl-containing materials and aromatic amines.
It has now been discovered that high molecular weight aminated polyols can be employed to enhance certain properties such as one or more of those selected from, for example, flexural modulus, tensile strength, tear strength, and the like in such RIM urethane systems usually without an unacceptable reduction in other properties of the polymer.